title: Clinical implication of crescentic lesions in immunoglobulin A nephropathy.
abstract: BACKGROUND
  To date, there has been much controversy about the role of crescentic lesion as a significant prognostic factor in immunoglobulin A nephropathy (IgAN). This study evaluated whether crescentic lesions predict adverse renal outcomes in IgAN patients.
  
  
  METHODS
  A total of 430 patients with biopsy-proven IgAN between January 2000 and December 2009 were included. Histological variables of the Oxford classification (Oxford-MEST) and the presence of crescents were assessed. The primary endpoint was a 50% decline in estimated glomerular filtration rate.
  
  
  RESULTS
  Of the 430 patients, 81 (18.8%) had a crescentic lesion. During a mean follow-up of 61 months, the primary outcome occurred in 19 (23.5%) patients with crescents compared with 40 (11.5%) patients without crescents (P=0.01). A Kaplan-Meier plot showed that the 10-year renal survival rate was significantly lower in patients with crescents than patients without crescents (P=0.01). However, in a multivariable Cox analysis which included clinical factors and the Oxford-MEST, crescents were not significantly associated with an increased risk of developing the primary outcome [hazard ratio: 0.71, 95% confidence interval (CI) 0.36-1.41, P=0.33]. Furthermore, adding crescents to the Oxford-MEST did not improve the discriminative ability for the prediction of renal outcomes [c-statistic: 0.86 (0.81-0.91) vs. 0.86 (0.80-0.91), P=0.21].
  
  
  CONCLUSIONS
  Crescentic lesion was not an independent prognostic factor, suggesting that crescents have limited value in predicting renal outcomes of IgAN.
authors.affiliation: Department of Internal Medicine, College of Medicine, Yonsei University, Seoul, Korea.
authors.forename: Mi Jung
authors.initials: MJ
authors.lastname: Lee
authors.forename: Seung Jun
authors.initials: SJ
authors.lastname: Kim
authors.forename: Hyung Jung
authors.initials: HJ
authors.lastname: Oh
authors.forename: Kwang Il
authors.initials: KI
authors.lastname: Ko
authors.forename: Hyang Mo
authors.initials: HM
authors.lastname: Koo
authors.forename: Chan Ho
authors.initials: CH
authors.lastname: Kim
authors.forename: Fa Mee
authors.initials: FM
authors.lastname: Doh
authors.forename: Tae-Hyun
authors.initials: TH
authors.lastname: Yoo
authors.forename: Shin-Wook
authors.initials: SW
authors.lastname: Kang
authors.forename: Kyu Hun
authors.initials: KH
authors.lastname: Choi
authors.forename: Beom Jin
authors.initials: BJ
authors.lastname: Lim
authors.forename: Hyeon Joo
authors.initials: HJ
authors.lastname: Jeong
authors.forename: Seung Hyeok
authors.initials: SH
authors.lastname: Han
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D005922:Glomerulonephritis, IGA / Q000150:complications / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D007668:Kidney / Q000473:pathology* / Q000503:physiopathology; D007676:Kidney Failure, Chronic / Q000453:epidemiology / Q000209:etiology / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D055815:Young Adult
keywords: Oxford classification; crescents; immunoglobulin a nephropathy; outcome